Patent GB-348648-A (GB)
Title: Improvements in web roll controlling and roll changing mechanisms for use with printing machines
IPC: B65H19/18
Filed: 1930-02-12
Abstract: 348,648. Feeding webs. HOE & CO., Ltd., R., 109, Borough Road. London.-(Hoe & Co., Inc., R.; 138th Street, New York, U.S.A.) Feb. 12, 1930, No. 4775. [Class 100 (i).] Web-roll changing and braking devices.-In a webrenewing mechanism for a printing-machine, a runring roll and a spare roll are mounted on a movable support and means, controlled by the running web roll, are provided for automatically moving the support to bring the spare roll into joining and running positions. Means are also provided for rotating the spare roll prior to the joining operation and for severing the expired web. In one construction, Fig. 1, the running roll R and the spare roll S are mounted in arms 6, 7 of a frame fixed to a shaft 3 which can be rocked in either direction by a reversible motor 22. A bar 27, Fig. 5, arranged above each roll and guided by slots 26, Figs. 1 and 5, in the frame of the machine, carries rollers 30, 31, 32 which engage the roll and follow it during the unwinding operation, and to the bar is secured one end of weighted brake straps 28 which engage the roll surface. When the running roll has nearly expired, a roller 37 on one end of the bar 27 operates a switch lever 42 to engage a contact 41 and thereby close the circuit of the motor 22 which thereupon turns the shaft 3 in an anticlockwise direction, raising the roll S, which has previously been provided with paste, into contact with driving wheels 44 driven by gearing from the press. The roll S is thus brought up to the speed of the expiring web and further movement of the shaft 3 brings the roll S into engagement with the old web and also presses the old web into engagement with a knife 71 fixed to the bar 27. The circuit to the motor 22 is then broken by the opening of switch contacts 74, 77 by a pin 82 on a plate 10 secured to the shaft 3, and another circuit to the motor, driving it in the opposite direction, is immediately closed by the closing of contacts 75, 78 by the pin 82. During this movement a cam 83<1> on the plate 10 closes switch contacts 74<1>, 77<1> in readiness for the next roll-renewing operation. When the shaft has returned to normal position a cam 83 opens the switch contacts 75, 78 to stop the motor 22. Pushbutton switches may be arranged in the circuits to permit of manual control of the motor independently of the automatic control described above and the circuits may also be arranged to slow down the press during the renewing operation. In another construction. Fig. 9, the running roll R and spare roll S are mounted on arms 111, 112 fixed to a shaft 110 which can be completely rotated by an electric motor. Brake straps 28 are secured at one end to arms 116 fixed on a rock shaft 117 and pass over pulleys loose on a shaft 120 and over pulleys 124 and carry adjustable weights 29. Arms 126 which follow the roll as it decreases in diameter are fixed to the shaft 120 to which is also fixed a short arm 127 arranged opposite to a pushbutton switch 131 carried by a projection 130 on an arm 129 loose on the shaft 120 and engaging a boss 132 on the end of the arm 111. When the roll is nearly exhausted, the arm 127 operates the switch 131 to close the circuit to the motor and the shaft 110 is turned to carry the spare roll S first into engagement with the constantly rotating driving rollers 44 and then into contact with the expiring web to effect the join. During this movement the expiring roll depresses the arms 116 thereby acting through arm 142 on shaft 117, link 143, and arms 144, 150 on a rock shaft 145 to compress a spring 151. The rock shaft 145 is provided with a pair of arms 148 connected by a bar 149 carrying a knife 71 and spring plungers 152. When, during the continued rotation of the shaft 110, the expiring roll moves clear of the arms 116, the spring 151 expands, bringing the knife 71 smartly into engagement with the old web to sever it, and the plungers 152 into engagement with the roll to stop its rotation. When the new roll reaches the normal running position the circuit of the motor is broken by the actuation of a switch 154 by a projection 155 on the boss of the arms 111, 112. Specification 348,658 is referred to.